Moneyless strategy-proof mechanism on single-sinked policy domain: characterization and applications

We completely characterize deterministic strategy-proof and group strategy-proof mechanisms on singlesinked public policy domain. The single-sinked domain can be used to model any allocation problem where a single output must be chosen in an interval with the assumption that agents’ preferences have a single most loathful point (the sink) in the interval, and the preferences are increasing as one moves away from that sink. Practical domains like this appear in political voting system where each voter has his most-hated candidate and alternative candidates are evaluated by their proximity to this candidate or in obnoxious location problem, where each agent prefers to have the obnoxious location to be distant from his own location, among others. Moreover, as applications of our characterization, we extend existing models and results and resolve several open questions from the literature.